Answer:
I think the answer is A.
Explanation:
Im on the same question. im taking the exam rn.
The answers are B: Adverbial clause and C: dependent clause.
A group of words that has the role of an adverb is called Adverbial clause. The sentence "Now<em> if there was</em> one thing that the animals were completely certain of" equals to: <em>Certainly</em> (adverb); or <em>Completely</em> certain (adverb modifying an adjective) and it is both an adverbial clause and a dependent clause (one tha cannot stand by itself).
It may be A or D But I think it could be A
The object of the sentence.